Degradation of phenyl C61 butyric acid methyl ester: Poly (3-hexylthiophene) organic photovoltaic cells and structure changes as determined by defect investigations

被引:1
作者
Nguyen, Thien-Phap [1 ]
Renaud, Cedric [2 ]
Reisdorffer, Frederic [1 ]
Wangc, Leeyih [3 ]
机构
[1] University of Nantes, Institut des Matériaux Jean Rouxel, CNRS, 44322 Nantes Cedex3
[2] University of Bordeaux 1, Laboratoire de Chimie des Polymères Organiques, 33607 Pessac
[3] National Taiwan University, Center for Condensed Matter Sciences, Taipei 10617, 1, Sec.4, Roosevelt Road
关键词
Charge-based deep level transient spectroscopy; Defects; Degradation; Organic solar cells;
D O I
10.1117/1.JPE.2.0210130
中图分类号
学科分类号
摘要
Stability of organic photovoltaic cells is the key issue for their commercialization. Despite intensive investigations to clarify the causes of failure of devices, the process of degradation is not yet well understood. In this work, we made use of the trap measurements by the charge-based deep-level transient spectroscopy to study devices that have been aged by continuous exposure to artificial sunlight for 20 h, and we compared the trap parameters to those obtained in freshly prepared samples. With regard to poly (3-hexylthiophene) (P3HT)-based devices, the P3HT:phenyl C61 butyric acid methyl ester blend cells showed an additional deep trap level and a higher trap density. In the degraded devices, all the existing traps in the fresh sample were found, and there was no creation of additional defect levels. The density of several trap levels in the polymer was strongly reduced after aging. Analysis of the results suggests that a phase separation in the photoactive blend has occurred, leading to a better organization of the polymer domains to lower defect states. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE).
引用
收藏
相关论文
共 41 条
[31]  
Paci B., Et al., Structural/morphological monitoring approach to stability and durability issues of photoactive films for organic solar cells, Chem. Phys. Lett., 504, 4-6, pp. 216-220, (2011)
[32]  
Ray B., Alam M.A., A compact physical model for morphology induced intrinsic degradation of organic bulk heterojunction solar cell, Appl. Phys. Lett., 99, 3, (2011)
[33]  
Hu Z., Gesquiere A.J., Charge trapping and storage by composite P3HT/PC<sub>60</sub> BM nanoparticles investigated by fluorescence-voltage/single particle spectroscopy, J. Am. Chem. Soc., 133, 51, pp. 20850-20856, (2011)
[34]  
Girtan M., Rusu M., Role of ITO and PEDOT: PSS in stability/degradation of polymer: Fullerene bulk heterojunctions solar cells, Sol. Energy Mater. Sol. Cells, 94, 3, pp. 446-450, (2010)
[35]  
Broms P., Et al., Calcium electrodes in polymer LEDs, Synth. Met., 74, 2, pp. 179-181, (1995)
[36]  
Crispin X., Interface dipole at organic/metal interfaces and organic solar cells, Sol. Energy Mater. Sol. Cells, 83, 2-3, pp. 147-168, (2004)
[37]  
Nguyen T.P., Renaud C., Interface effects on the defect state formation in organic devices, Organic Photonic Material and Devices XI, Proc. SPIE, 7213, 1, (2009)
[38]  
Janssen F.J.J., Denier Van Der Gon A.W., Van Ijzendoorn L.J., Thoelen R., De Voigt M.J.A., Brongersma H.H., The influence of surface treatments on cathode formation and stability in polymer light emitting diodes, Applied Surface Science, 241, 3-4, pp. 335-351, (2005)
[39]  
Zhu J., Et al., Formation of the calcium/poly (3-hexylthiophene) interface: Structure and energetics, J. Am. Chem. Soc., 131, 37, pp. 13498-13507, (2009)
[40]  
Kawano K., Adachi C., Evaluating carrier accumulation in degraded bulk heterojunction organic solar cells by a thermally stimulated current technique, Adv. Funct. Mater., 19, 24, pp. 3934-3940, (2009)